At twenty years or more, elevator product life is long, but various technologies improve during that time. Energy is saved in elevators also by new technology being developed, user convenience is improved by new elevator features, etc., and user waiting time is shortened by improvements in elevator operating efficiency, etc., generating demand to renovate elevators. When elevators are refurbished, there is also demand for refurbishing to be done without losing elevator operating efficiency during refurbishment transition periods.
As an elevator refurbishing method that has been proposed to meet these requirements, it has been proposed that a device for connecting an existing group supervisory device and a new group supervisory device be used-when refurbishing so as to minimize deterioration in overall elevator services when replacing an existing elevator with a new elevator (see Patent Literature 1, for example).